With Nikon introducing their FX-sensor there is a lot of expectation as to what you can expect from the D3 or other FF-sensor bodies like those from Canon in comparison to the APS-C sensor bodies.
With respect to photon-collection, everything seems clear: with 2x* the size of a single FF/FX-photo cell you collect double the photons in each cell.
This in turn means that with the same exposure you catch 2x the photons in one cell than with an APS-C size sensor cell and that is 2x the number of electrons that FF/FX-cell can generate. So s/n-ratio should be 2x better. All clear?
Not quite! Last time I checked, larger electronic structures generate inherently higher noise
But for the sake of simplicity and as all the results point to a 1 stop (i.e.2x) better s/n-ratio let's assume that is so.
This means that you get the same noise with a FF/FX-sensor at ISO 1600 than with an APS-C sensor at ISO 800. Or: You can expose -1EV on the FF/FX-sensor to get the same results as with the APS-C sensor.
Now on to dynamic range: With this -1EV exposure on the 2x larger photo-cell you should just capture the same amount of photons and generate the same amount of electrons from it as on the APS-C sensor with normal (0EV) exposure. But as the larger photosite has 2x the capacity for photons than the smaller cell it should be capable of having +1EV more dynamic range.
Has anyone any evidence confirming (or disprove) my deductions?
Any meaningful tests with Canon's FF-bodies on DR??
And what about larger electrical noise in larger electronic structures???
*I'll stick to 2x in this article just for simplification! In reality the FF/FX_sensor has 2.5x the size of an APS-C sensor and each photosite is 2.5-3x larger!
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